Ask HN: How do you keep your motivation up during the day?

When I wake up I have my coffee and soon I start feeling very motivated. My first hour is usually full of great ideas an a high level of motivation. But then I can feel how it goes away very quickly.

I love that boost in the morning. In rare occasions I can extend it for a few days because I'm working on something very exciting.

I feel like there are certain tasks that I do that generate certain level of emotional distress on me. I love my job but after a couple of hours doing something I can feel like shit. That never happens when I go out for a walk or ride my bike or when I hang out with my friends.

What does this mean? How can I fix it? For some context, I think that generally I perform very well at work but I have this constant fight with my inner self that I wish I didn't have to deal with.

Am I alone?